Huge aftershocks hit Japan; 763 dead so far

As Japan dealt with a major nuclear meltdown threat, it also struggled to determine the scope of the earthquake, the most powerful in its recorded history, and the tsunami that ravaged its northeast Friday with breathtaking speed and power. The official count of the dead was 763, but the government said the figure could far exceed 1,000.

Meanwhile, Japan's meteorological association upgraded the Saturday quake's magnitude from 8.8 to 9 on the Richter scale, making it tied for the fifth largest earthquake in history. The agency said there were three successive earthquakes.

Teams searched for the missing along hundreds of miles of the Japanese coast, and thousands of hungry survivors huddled in darkened emergency centers that were cut off from rescuers and aid. At least a million households had gone without water since the quake struck. Large areas of the countryside were surrounded by water and unreachable. Some 2.5 million households were without electricity.

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Powerful aftershocks continued to rock the country, including one Sunday with a magnitude of 6.2 that originated in the sea, about 111 miles east of Tokyo. It swayed buildings in the capital, but there were no reports of injuries or damage.

Two days after the magnitude 8.9 quake, there were grim signs that the death toll could soar. One report said no one could find four whole trains. Others said 9,500 people in one coastal town were unaccounted for and that at least 200 bodies had washed ashore elsewhere.

The government said 642 people were missing and 1,426 injured.

Atsushi Ito, an official in Miyagi prefecture, among the worst-hit states, could not confirm the figures, noting that with so little access to the area, thousands of people in scores of towns could not yet be reached.

"Our estimates based on reported cases alone suggest that more than 1,000 people have lost their lives in the disaster," Edano said. "Unfortunately, the actual damage could far exceed that number considering the difficulty assessing the full extent of damage."

Japan, among the most technologically advanced countries in the world, is well-prepared for earthquakes. Its buildings are made to withstand strong jolts - even Friday's, the strongest in Japan since official records began in the late 1800s. The tsunami that followed was beyond human control.

With waves 23 feet high and the speed of a jumbo jet, it raced inland as far as six miles, swallowing homes, cars, trees, people and anything else in its path.

"The tsunami was unbelievably fast," said Koichi Takairin, a 34-year-old truck driver who was inside his sturdy, four-ton rig when the wave hit the port town of Sendai. "Smaller cars were being swept around me. All I could do was sit in my truck."

His rig ruined, he joined the steady flow of survivors who walked along the road away from the sea and back into the city Saturday.

Smashed cars and small airplanes were jumbled against buildings near the local airport, several miles from the shore. Felled trees and wooden debris lay everywhere as rescue workers in boats nosed through murky waters and around flooded structures.

The tsunami set off warnings across the Pacific Ocean, and waves sent boats crashing into one another and demolished docks on the U.S. West Coast. In Crescent City, California, near the Oregon state line, one person was swept out to sea and had not been found Saturday.

In Japan early Sunday, firefighters had yet to contain a large blaze at the Cosmo Oil refinery in the city of Ichihara. Four million households remained without power. The Russian news agency RIA Novosti reported that Japan had asked for additional energy supplies from Russia.

Prime Minister Naoto Kan said 100,000 troops had joined the rescue and recovery efforts, helped by boats and helicopters. Dozens of countries offered to pitch in. President Barack Obama said one American aircraft carrier was already off Japan and a second on its way.

Two other U.S. rescue teams of 72 personnel each and rescue dogs were scheduled to arrive later Sunday, as was a five-dog team from Singapore.

Aid had just begun to trickle into many areas. More than 215,000 people were living in 1,350 temporary shelters in five prefectures, the Japanese national police agency said.

"All we have to eat are biscuits and rice balls," said Noboru Uehara, 24, a delivery truck driver who was wrapped in a blanket against the cold at a shelter in Iwake. "I'm worried that we will run out of food."

The transport ministry said all highways from Tokyo leading to quake-stricken areas were closed, except for emergency vehicles. Mobile communications were spotty and calls to the devastated areas were going unanswered.

Although the government played down fears of radiation leak, Japanese nuclear agency spokesman Shinji Kinjo acknowledged there were still fears of a meltdown -- the collapse of a power plant's systems, rendering it unable regulate temperatures and keep the reactor fuel cool.

Yaroslov Shtrombakh, a Russian nuclear expert, said it was unlikely that the Japanese plant would suffer a meltdown like the one in 1986 at Chernobyl, when a reactor exploded and sent a cloud of radiation over much of Europe. That reactor, unlike the reactor at Fukushima, was not housed in a sealed container.